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By K. E. Merklin, F. D. DeVaney

Students of the modern blast furnace seem unanimously agreed that they are observing a major revolution in practice. Rather than changing construction and operation of the furnaces, most of the great advances now under way deal with the raw materials feed. Prepared burdens have gained increasing significance during recent years. Sizing, concentration, and agglomeration have all become bywords to greater production and reduced operating costs. The remarkable results with test furnaces in which self-fluxing sinter makes up part or all of the ore charge foretell even greater improvements. Other investigators have reported many of these advances, and it is enough to predict here that more and more operators will turn to the use of self-fluxing sinter.

Jan 3, 1960

By W. F. Guenther

The usual hand-operated drilling outfit consists of a 4-in. post-hole auger with 3/4,-in. pipe for drill stem, in 4-ft lengths, with a turning handle fitted to a top pipe T. The auxiliary tools are: a chisel-bit drill made from 3/4 or 7/8-in. tool steel welded to a 4-ft length of 3/4-in, pipe, so that the regular pipe string can be used; also a churn or "mule foot" made from 3-in. pipe, slotted on one side, belled to a 4-in. tempered cutting edge on the bottom, all welded to a 3/4-in. coupling by a yoke. Other tools required are pipe wrenches and cleanout tools made from old auto springs (Fig I). A 4 1/2 or 5-in. collar welded to a plate is often used to protect the mouth of the drill hole. In general the auger is used in the typical clay overburden and brown phosphate matrix, which is relatively soft. The churn or "mule foot1' is used in hard pan, lump phosphate or cherty ground. The drill is used for breaking flint, often found loose in the overburden. The drill with the chisel bit is used for trimming sides of the hole, sounding for lime bottom and breaking through hard lumps. Holes have been drilled to a depth of 80 ft, but the limit of efficient operation is about 50 ft. In deep holes it is necessary to unscrew the string in 20-ft lengths, to

Jan 1, 1948

By E. R. Borcherdt

IT is notable that the first large-scale mine operation equipped entirely with detachable bits was the Badger State mine of the Anaconda Copper Mining Co. in Butte, Montana, just 30 years ago. This mine in 1922 was producing approximately 1200 tons of ore per day. Much of the data presented in C. L. Berrien's article1 describing the development and installation of the Hawkesworth detachable drill bit were obtained from these operations. As in any pioneering effort, no precedent existed and many difficult problems required solution, so that the changeover to detachable bits at all Butte hill mines was not completed for 6 years. There was widespread disbelief as to the probable efficiency of the new installation.

Jan 2, 1953

By F. J. Zuiderweg, G. G. Bemer

Results of a study aimed at assessing kinetics and mechanisms of the batch agglomeration process in suspension are discussed. A recently developed light backscatter technique which enables the increase of average particle size from 1 to 5000 µm to be followed, was used to determine agglomeration kinetics. Growth curves and agglomerate size distributions were obtained in a stirred vessel for various model systems and operating conditions. Four distinct growth regimes were identified, i. e. the flocculation regime, the zero-growth regime, the fast growth regime, and the equilibrium regime. Further, it was observed that large differences in the occurrence and duration of these regimes resulted from small variations in parameters, such as size distribution of the initial particles and the binding-liquid to solid ratio. Mechanisms that determine the occurrence of the relevant regimes are discussed. The growth process was described in terms of population balance equations. In this way, the growth rate, the equilibrium agglomerate size distribution, and the evolution of the agglomerate size distribution were generated. The agreement with experimental results is satisfactory.

Jan 1, 1980

By David Mandolesi

An examination has been made of the structures of strand cast blooms and the rails rolled from them; this paper details the characteristics of these typical structures. Results of mechanical testing data show that this product compares with rails processed from conventional ingot steel. Improvement in processing yields and surface quality standards are also briefly discussed.

Jan 1, 1972

By Alfred Brooks

Introduction PETROLEUM seepages are known in Alaska at four localities, all on Pacific seaboard. These, named from east to west, are Yakataga, Katalla on Controller Bay, Iniskin Bay on Cook Inlet, and Cold Bay on the Alaska Peninsula. Besides these, a petroleum residue has been found near Smith Bay on the north Arctic coast of the Territory. At Katalla, Cold Bay, and Iniskin Bay there has been some drilling for oil, and in the first field several productive wells have been opened up. Alaskan petroleum so far as its composition is known, is a refining oil, with paraffin base and low sulphur content. Most of what is known of the geology of Alaska oil fields is based on the investigations of Dr. George C. Martin, of the United States Geological Survey. A. G. Maddren, of the same service, has recently made a reconnaissance of the Yakataga oil field. The data to be here presented are chiefly taken from the following publications: G. C. Martin: The Petroleum Fields of the. Pacific Coast of Alaska, with an account of the Bering River coal deposits, Bulletin No. 250, U. S. Geological Survey, pp. 9 to 27 (1905). G. C. Martin: Geology and Mineral Resources of the Controller Bay Region, Alaska, Bulletin No. 335, U. S. Geological Survey, pp. 112 to 130 (1908). G. C. Martin and F. J. Katz: A Geologic Reconnaissance of the Iliamna Region, Alaska, Bulletin No. 485, U. S. Geological. Survey, pp. 126 to 130 (1912). A. G. Maddren: Mineral Deposits of the Yakataga District, Bulletin No. 592,. U. S. Geological Survey, pp. 143 to 147 (1914).

Jan 2, 1915

By G. H. Billings

There exists an unconfirmed opinion among many ironmasters that the combination of a small quantity of manganese, chromium, titanium, tungsten, aluminium, nickel, and some of the metalloids with iron has a beneficial effect upon the quality. And the impression prevails in some localities that the excellence of steel greatly depends upon the influence of some of these elements. Brit as the recorded experiments are so meagrely described, and made under such various conditions, the student in search of information upon the subject is somewhat bewildered by the contradiction of the opinions expressed. Observing some interesting phenomena while experimenting with an alloy of iron, copper, and nickel, I was led to determine the effect of some of the metals upon iron as free from contamination by other elements as it is possible to procure in practice, in order that the result of an alloy of an individual metal with iron might be more closely studied; for it is almost an impossibility to determine the influence of a small amount of one element upon a metal combined with a large amount of another, and the mere presence of another sometimes makes this difficult. And as most of the experiments recorded upon this subject have been made with iron containing sufficient carbon and other elements to interfere with the effect of that metal the influence of which it was desired to observe, I have endeavored to avoid these sources of error as far as practicable. In determining the specific gravity of the alloys in these ex-

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Jan 1, 1938

By Charles Hart

THE art of electric smelting came with the turn of the present century and owes its existence to the introduction of alter-nating current, which found its first wide use in the establishment of the great power plants at Niagara Falls, N, Y. Prior to that time current was largely direct. The fur-naces were electrolytic in nature and found their first metallurgical use in the produc-tion of aluminum, and this process still prevails. The normal production of pig iron up to that time was carried on in blast furnaces in which charcoal, coke and anthracite were used as the fuel. This new electric process called for sufficient carbonaceous material to reduce the oxides and impregnate the pig iron with sufficient carbon, but the remainder of the energy was to be supplied by electric power. The chemical reactions are essentially the same in electric smelting as obtains in the older blast furnace. All of these data are so well known in both methods as to need no discussion at this time, for they can be found in scientific publications and books written during the first two decades of this century.

Jan 1, 1940

By Harold Bloom, H. E. Hawkes

Streams and rivers are the principal channels into which the weathering products of rocks and their contained ores are funneled. The inorganic load of a stream system is a crude sample of all the earth materials in the drainage basin of the stream, and the heavy mineral assemblage of sediments is one of the oldest and most successful guides to certain kinds of bedrock ore in unexplored terrain. Early application of this method was made possible by the ease of separation and identification of heavy minerals in the field with the simplest equipment. Water analysis for traces of base metals became a practical possibility about eight years ago with the development of rapid chemical tests that could be carried out at the field site. Since that time the water method has been widely used in mineral reconnaissance, and a substantial number of discoveries have been reported. Here again, the techniques developed for this work were relatively simple and could be performed easily at the field site.

Nov 1, 1956

By J. C. Bartlett

(Read at the Wilkes-Barre Meeting, May, 1877.) THE following discussion was suggested by an experiment of Mr. Krom, the manufacturer of air-jigs, to illustrate the superiority of air over water as a medium of concentration. The paper is written in the interest of no system of concentration, but simply to test the experiment, and, perchance, to add something to the general fund of information on the subject. To speak of testing an experiment by a theoretical discussion, may seem a misuse of terms, but the theories concerning falling bodies and the resistance of fluids are pretty well crystallized into laws, which may properly be used to show where experiments which seem to refute them were improperly performed, and that instead of refitting they only corroborate. It is well known that a sphere of galena 1/8 inch in diameter, and a sphere of quartz 1/2 inch in diameter, are equal falling in water ; that is, these two spheres, being placed together in a column of water at rest or in motion, will practically remain together, falling or rising together, or remaining in suspension. Mr. Krom, to show that these

Jan 1, 1878

During the presentation of the papers, questions were deferred until after the last paper in the afternoon. At that time, the authors and co-chairmen formed a panel for discussion of any pertinent questions. The panel was as follows: Carl Gerity - Ozark Lead Company – Chairman Mike Young - Master Mechanic - Ozark Lead Company Largo Albert - Maintenance Specialist (hoisting) Mines Maintenance Dept. - International Nickel Company, with assistance from Co-author Alan Cameron - International Nickel Company Gary Beerkircher - Product Manager - Rexnord Inc., Nordberg Machinery Group Richard Schaal - Director of Maintenance - Superior Division, Magma Copper Company Rich Hodgson - Assistant Production Superintendent - FMC Corporation The remarks have been edited by the panelists for readability, the basic ideas were not changed. Additional thoughts by the panelists submitted at the time of their revision are indicated by ***.

Jan 1, 1975

By H. M. Chance

The iron-ore deposits of the Hartville district are located near the new town of Guernsey, about 100 miles north of Cheyenne. The writer has been familiar with them since 1887, having visited the district several times for different clients— his last examination having been made in November and December, 1897. The deposits extend in a general N.E.-S.W. direction from a point in Section 33, Range 65 W., Township 28 N., on the west side of Whalen cañon, through Sections 4, 5, 6, 7 and 8 of Township 27 N. in the same Range, and over into Sections 1 and 12 of Township 27 N., Range 66 W. General Characteristics. The ore is a remarkably pure red hematite, extremely low in phosphorus, and carrying a small percentage of silica, as shown by analyses given below, and similar in many respects

Jan 1, 1901

By M. Amsterdam, F. Rothwarf, L. Muldawer

SILVER-cadmium near the composition AgCd shows three equilibrium phases. As with 13 brass, the high temperature phase is disordered body-centered cubic (8) and the low temperature phase has the ordered CsCl structure . However, there is an intermediate temperature phase which is hexagonal close-packed ((). In a recent paper, Speich and Mack' report on a study of the Ag-Cd eutectoid near the AgCd composition. Unfortunately, the phase diagram upon which they base some of their conclusions is incorrect. That diagram is taken from the Metals Handbook' and the error is that the 0 and ( phases have been interchanged. The Handbook gives the low temperature phase as hexagonal (designated 5) and the intermediate temperature phase as cubic ordered (designated . The error may be typographical or it may be one of confusion resulting from the use of 5, ,, and 0 for the intermediate phase in various papers. A careful search of the literature reveals that a number of authors have indicated the correct relative positions of the 13, 5, and 0 phases. The comprehensive work of Fraenkel and Wolf clearly stated that the high and the low temperature phases are either identical or are very similar. olander,' on the basis of electrochemical measurements, showed that the 13 phase is disordered and the 1 phase (designated 8" in his paper and in refs. 3 and 5) is ordered. Further work by Durrant5 using thermal and metallographic analyses provided a more precise phase diagram. A summary of these works was given by Hansen6 and shows the correct relative positions of the phases. Owen, Rogers, and Guthrie7 located correctly the upper two phases by X-ray diffraction. Their failure to find the low tem-

Jan 1, 1954

By W. F. Guenther

The usual hand-operated drilling outfit consists of a 4-in. post-hole auger with 3/4,-in. pipe for drill stem, in 4-ft lengths, with a turning handle fitted to a top pipe T. The auxiliary tools are: a chisel-bit drill made from 3/4 or 7/8-in. tool steel welded to a 4-ft length of 3/4-in, pipe, so that the regular pipe string can be used; also a churn or "mule foot" made from 3-in. pipe, slotted on one side, belled to a 4-in. tempered cutting edge on the bottom, all welded to a 3/4-in. coupling by a yoke. Other tools required are pipe wrenches and cleanout tools made from old auto springs (Fig I). A 4 1/2 or 5-in. collar welded to a plate is often used to protect the mouth of the drill hole. In general the auger is used in the typical clay overburden and brown phosphate matrix, which is relatively soft. The churn or "mule foot1' is used in hard pan, lump phosphate or cherty ground. The drill is used for breaking flint, often found loose in the overburden. The drill with the chisel bit is used for trimming sides of the hole, sounding for lime bottom and breaking through hard lumps. Holes have been drilled to a depth of 80 ft, but the limit of efficient operation is about 50 ft. In deep holes it is necessary to unscrew the string in 20-ft lengths, to

Jan 1, 1948

By K. Matsuda, H. Tanaka, M. Mamiya, H. Majima

Copper cementation was studied from both thermodynamic and kinetic aspects. The temperature effect of copper cementation, which has been recognized as an anomalous result, and the rate enhancement phenomenon observed after the initial linear step are, in particular, focused in this work. The main results obtained are as follows; 1) Free energy changes of copper cementation reactions, calculated by the use of the "Correspondence Principle" of Criss and Cobble are rather insensitive to temperature. 2) A Flow-cell assembly consisting of a special cupric ion electrode, a calomel electrode and a potentiometer is particularly useful for the continuous measurements of copper cementation rate. 3) Two first-order reaction rate constants for the CU2+- Fe system were successfully determined by the use of the flow-cell assembly. 4) Activation energies determined for the initial rate and the 9 maximum rate of CU2+ - Fe system are both 4.6 kcal/mole. This fact suggests that the mechanisms of the initial reaction and the final reaction are essentially the same and both reactions are rate controlled by the diffusion in a boundary layer. The difference in the rate constants of them may fie explained by the effect of the nature of surface deposits. 5) Qualitative explanation of the rate enhancement phenomenon from the initial rate was successfully made by applying Bockris "Penetration Model."

Jan 1, 1976

By C. W. Ryan

THIS paper contains a brief sketch of the geology of soapstone in the Piedmont section of Virginia, in the southern portion of Nelson County; also a description of methods of prospecting, developing quarries, quarrying and and milling methods in that section. The paper is intended for those who have little information regarding soapstone; undoubtedly men of practical experience will find many points for criticism.

Jan 1, 1929

By N. J. King, R. F. Hadley

Alluvial valley floors constitute a valuable land resource and are important to ranching operations in the semiarid western United States. This resource may be in jeopardy locally if the alluvial deposits are disturbed by surface mining of coal deposits. Erosion problems caused by poor land-use practices can cause trenching of the unconsolidated alluvium with a consequent lowering of the water table and depletion of soil moisture needed to support vegetation. Historical evidence of this sequence of events is abundant in the geologic literature and serves as the basis for assessing potential impacts of surface mining. The potential geomorphic impacts of surface mining on alluvial valley floors with regard to fluvial processes are. (1) disruption of the longitudinal profile followed by valley trenching and high sediment yields downstream, and (2) replacement of the excavated alluvium with unconsolidated material that does not have similar physical characteristics and may be susceptible to erosion. Mining may disrupt the existing hydrologic framework affecting stream flow, ground-water levels, and water quality of both surface and ground water. Although functional hydrologic and geomorphic processes are similar, each valley represents a complex environment that does not submit to broad generalizations.

Jan 1, 1981

By Felicia F. Peng

The computer graphic routines and digital simulation program of coal cleaning circuits have been developed in the Mineral Processing Engineering Department, West Virginia University. The functions of the program include computing, tabulation and graphing of 1) washability characteristics of raw coals, 2) blending, 3) Tromp distribution curves for two washer types-- water only and dense medium, 4) predicting the functional relationship of yield and qualities of clean coal product in individual and overall coal cleaning circuits in coal preparation plant, and 5) determining the optimal clean coal yield based on the market and environmental specifications. Amdahl 470 V/7A digital computer, Tektronic 4025 graphic terminal and Tektronix 4663 digital plotter with Fortran IV are used to achieve the goals. The simulation with the aid of graphic routine program of coal cleaning circuits is a useful tool for coal preparation engineers in evaluating the feasibility of proposed flowsheets, in investigating the effect of a modification in a unit operation of an existing plant, in analyzing the off-line optimization, and in comparing the alternative circuit control strategies. The coal cleaning process simulation with graphic routine can contribute greatly to the decision making processes of preparation plant design.

Jan 1, 1983

By Walter R. Hibbard, Robert I. O’Herron, Fred D. Rosi, Howard T. Clark

INTRODUCTION AND PREVIOUS WORK IN the search to find a copper-base alloy with high strength properties, it was considered that the addition of a small amount of an age-hardening element to a binary system with useful strength properties might result in a series of alloys of theoretical and practical importance. [ ] The copper-nickel system was selected for its basic properties and chromium was added as the age-hardening element in view of the small percentage involved and its decreasing solubility with decreasing temperature. A study of the Cu-Cr binary alloys was undertaken as a preliminary investigation. However, in view of the response of these alloys to heat treatment, the scope of this phase of the investigation was widened. [ ]

Jan 1, 1948